Furnace



June 14, 1932. .1. A. MIRZEJEwsKi FURNACE Filed July 17, 1929 INVENTOR www ATTORNEY /w al Patented June 14, 1932 Unirse stares PATT OFP'ICII` Y JOHN A. MIRZEJEW'SKI, 0F WEST ALIIS, WISCONSIN, ASSIGNOR TO KEARN EY & TRECKER CORPORATION, OF WEST' ALLIS, WISCONSIN' FURNACE Application led July 17,

This invention r-elates to an improved furnace, particularly for heat treating and similar purposes.

A purpose is to provide a furnace operated from a fuel such as gas and capable of substantially uniform heat distribution througlr out the charging or work chamber.

A further purpose is to obtain such substantially uniform heat distributon from a single fuel burner or flame jet.

A further purpose relates to a furnace having a single burner or flame j et positioned for greatest convenience of adjustment and operation, and from which the heat may be directed or distributed in a manner such that the temperature of the charging space or work chamber may be substantially uniform.

A further purpose relates to the control of a furnace such as mentioned above in a manner such that portions most dilicult or slow to heat may be subjected to eXtra heat when the hea-t of the furnace is being raised yet the final temperature may be substantially uniform throughout the Work chamber and work pieces therein.

Gther purposes are generally7 to simplify and improve the construction and operation of heat treating furnaces and still other objects will be apparent from the accompanying specification.

The invention consists in the particular construction herein illustrated, described and claimed and in such modifications thereof as may be equivalent to the claim. l

In the drawing the same reference characters have been used for the same parts in each view.

Fig. 1 is a vertical section from front to rear of a furnace of the hearth type which includes the invention, and taken along line 1 1 of Fig. 3.

Fig. 2 is a vertical transverse section of the same furnace taken along lne 2 2 of Fig. 1.

Fig. 3 is a horizontal section taken along line 3 3 of Fig. 1.

The furnace in this case consists of a heat retaining or insulating structure or framework of suitable material and providing a lower chamber 1 and an upper chamber 2 adapted to receive the parts to be treated.

1929. Serial No. 378,884.

Chamber 2 is provided with an opening 3 through which parts are inserted or withdrawn and which is closed during operation of the furnace by means of a closure generally denoted as 4, which is arranged to move vertically, and counterbalanced in such movement by suitable devices such as cable 5, pulley 6 and Weight 7, Fig. 1.` i

The lower chamber 1 receives heat directly from a burner 8 arranged at the front of the furnace to direct its llame into the chamber 1 through an opening 9 through the Wall thereof, the burner being supplied With fuel in any suitable manner, preferably such that the name and accompanying hot gases are directed into chamber 1 with considerable force and velocity. The force of the heat jet from burner 8 is directed toward the back Wall 10, Fig. 1, and from there is deflected back along the sides of the chamber 1 to rise into the chamber 2 through openings or channels 11, 12, 13, 14, 15, 16, arranged along one side Wall of the furnace, and through openings orchannels 1'?, 18, 19, 20, 21, 22, similarly arranged along the other side wall.

The various openings just mentioned are graduated in size or effective area according to their position relative to the point of greatest gas pressure in chamber 1, which in this case is adjacent the rear wall thereof. The rela.- tive area and position of each opening'is such that each has substantially .the same heating effect on chamber 2, and also'such that the gases directed to the different openings will substantially equally heat the walls over which they pass. f

Channels 23, 24, 25 are provided at the front of the furnace, in this case being partly formed in the door or closure 4. These chan.- nels are similar and each includes a manually operable obstruction or damper, similar to a damper shown for channel 24 in Fig. 1, and including a pivoted member 26 operable by a lever or handle 27,-fto positions effective to substantially close or to open the channel, and to various intermediate positions.

Channels 28, 29, 30 are provided at the rear of the furnace, in this case being formed in the wall structure. These channels are similar and each includes a manually operable obstruction or damper similar to a damper 31, Fig. 1, shown for channel 29 and consisting of a member 32 resting on the top wall of the furnace and manually shiftable to positions effective to substantially close or to open the channel and'to various intermediate positions.

The heated gas passing through openings 11,12,13,14f,15,16 and openings 17,18,19,20, 21, 22, does not pass directly from such openings into chamber 2, but instead rises through channels such as channels 33, 34, shown iii Fig. 2 for openings 11, 17, respectively. Thus the gas is all directed upwardly to impinge on the roof of the chamber 2. The gas thence moves downwardly through chamber 2 to pass out of the various front channels 23, 24, 25, or the rear channels 28, 29, 30, or such of them as may be in use, and each of which may be controlled yby the dampers previously described to determine the proportionof gas accepted by each channel.

The arrangement is such' that all the walls of the chamber 2 will be substantially uniformly heated because of the previously mentioned graduated size and relative position of the openings which control the flow of heated gas through or past such walls. But in the operation, various work pieces differently positioned within chamber 2 may materially change the heat absorbing characteristics for the combination whereby one portion of the chamber will require a materially higher rate of flow of heat theretothan others in order that all load of the furnace may simultaneously arrive at a predetermined heat as quickly as may be possible. This may be readily accomplished bymanipulating the dampers previously described to direct the flow of hot gases through the chamber.

What is claimed is:

In a furnace the combination of a substan-V tially box-like housing forming substantially box-like upper and lower chambers, a heat source adapted to direct aA heated gaseous blast through a side wall of said housing and substantially horizontally into said lower chamber and in the direction of another wall thereof opposite said side wall, passageways from said lower to said upper chamber and leading from various points adjacent the top wall of said lower chamber, intermediate portions of said passageways being of different resistance to the passage of gas therethrough in accordance with the relative distance of different of said passageways from said other wall, each of said passageways opening into said upper chamber adjacent the top wall thereof, said upper chamber having an opening through aside wall thereof and a movable closure for said opening, and a plurality'of outlets from said upper chamber, one of said outlets including a channel through said movable closure and the other including a channel through a wall of the upper chamber opposite the last mentioned side wall, the openings from said upper chamber into said channels being positioned adjacent the bottom wall of said upper chamber.

In witness whereof I have hereto ailixed my signature.

JOHN A. MIRZEJEWSKI. 

